In general, to store food, or the like, which may easily decay at room temperature, a sealed container is commonly used.
However, through only a simple sealing operation, the decay of food can be somewhat delayed, but it may be difficult to prevent the decay of food altogether. Therefore, contents accommodated in a sealed container are stored in a refrigerator after being opened. In particular, in the case of wine in a bottle, once a stopper is removed, air slowly flows into the bottle, even if the stopper is inserted back into the bottle thereafter. Thus, wine is in contact with oxygen and becomes oxidized, whereby quality drops.
In order to store wine, food, or the like, which may easily decay, even at room temperature, for an extended period of time, a vacuum container has been proposed.
However, the vacuum container should be integrally equipped with a relatively complex pumping means for the formation of a vacuum in at least a container lid. Therefore, as costs of manufacturing a vacuum container increase, consumers are burdened with higher purchase costs.
Korean Utility Model Registration No. 0445177 disclosing a vacuum pump for a container stopper proposes a configuration in which a vacuum pump, a vacuum generating means, is provided separately from a container. In Korean Patent Laid-open Publication No. 2010-0045673, a configuration of sealing a container by providing a stopper for pumping, such as a pumping stopper, in an inlet of a container such as a bottle to combine the separate vacuum pump with the container is proposed. In addition, a stopper for a vacuum container is proposed in Korean Utility Model Laid-open Publication No. 2010-0008443.
However, even if such a stopper stably blocks an inlet due to vacuum pressure inside a container, over time, air flows into the container, so vacuum pressure inside the container is gradually lowered. Thus, if a certain period of time has elapsed, an actual vacuum inside the container may be completely released.